Existential neuroscience: neurophysiological correlates of proximal defenses against death-related thoughts

摘要

A great deal of evidence suggests that reminders of mortality increase ingroup support and worldview defense, presumably in order to deal with the potential for anxiety that roots in the knowledge that death is inevitable. Interestingly, these effects are obtained solely when thoughts of death are not in the focus of consciousness. When conscious, death-related thoughts are usually defended against using proximal defenses, which entail distraction or suppression. The present study aimed at demonstrating neurophysiological correlates of proximal defenses. We focused on the late positive potential (LPP), which is thought to reflect an increased allocation of attention toward, and processing of, motivationally relevant stimuli. Our prediction was that the LPP should be increased for death-related relative to death-unrelated, but equally unpleasant stimulus words. In Experiment 1, this prediction was confirmed. This finding was replicated in Experiment 2, which used a target word detection task. In Experiment 2, both death-related and pleasant words elicited an enhanced LPP, presumably because during the less demanding task, people might have distracted themselves from the mortality reminders by focusing on pleasant words. To summarize, we were able to identify a plausible neurophysiological marker of proximal defenses in the form of an increased LPP to death-related words.